This program project deals with four aspects of nervous system function: 1) Excitable membranes; 2) Sensory and synaptic transduction at the cellular level; 3) Information transfer from sense organs to the CNS; and 4) Nerve trophism and regeneration especially in sensory systems. The project involves 13 investigators who have collaborated in several aspects of these problems. These studies involve ionic mechanisms in excitable tissue, sensory transduction in chemo- and photoreceptors, sensory information from the retina and skin receptors, nerve regeneration and inductive properties of pre-neural elements on sensory fibers. A multidisciplinary approach (electrophysiological, neurochemical and neuroanatomical) will be employed to solve these problems. This has proven successful in the past and it is expected that continued success will be possible by the support requested in this application. Support is requested for core facilities (equipment, supplies and personnel salaries) and, on a modest scale, for some individual research projects.